1 Galapagos tortoises are the world's largest tortoise species. They measure up to four feet long and weigh as much as 700 pounds. Tortoises and turtles are actually the same animal. Yet, they are called these different names based upon the type of habitats in which they dwell. Tortoises live on land, and turtles live in water.2 As their name suggests, Galapagos tortoises live on the Galapagos Islands, about 650 miles off the coast of Ecuador. These brown-colored giants have huge carapaces (upper shells). Their shells resemble either domes or saddle-backs. What decides the type of shell they have? The simple answer to that is their diet.3 Galapagos tortoises with domed shells live on wetter islands where grasses thrive. But domed carapaces are a hindrance to Galapagos tortoises living on drier islands. Since these tortoises eat taller vegetation (such as shrubs and cactuses), they need to have shells that allow them to extend their necks. Hence, they have saddle-backed carapaces. Saddle-backed Galapagos tortoises have longer necks and front limbs than their domed cousins. Interestingly, the word "Galapagos" means "saddle-backs" in Spanish. So, Galapagos Islands -- in a literal translation -- are really islands of saddle-backed tortoises.